Piano accordion



Jan. 31, 1 950 w. B. AHERN ET AL 2,495,914

PIANO ACCORDION Filed March 25, 1947 2 Sheets-Sheet 1 Jan. 31, 1950 w. B. AHERN ET AL 2,495,914

PIANO ACCORDION Filed March 25, 1 947 v 2 Sheets-Sheet 2 Patented Jan. 31, 1950 PIANO ACCORDION William B. Ahern'and Albert J. Walt,.De Kalb,

Ill., assignors to The Rudolph Wurlitzer Company, Chicago, 111., a corporation Application March 25, 1947, Serial No. 737,082

This invention relates to a piano accordion and particularly to the treble section and treble shift mechanism therefor.

The particular feature of the invention herein involved resides in the construction and operation of the centrally mounted treble shift mechanism for actuating the slide valves controlling the harmonics of the reed blocks.

Another feature of the invention resides in the 'structure of the treble windbox and valve board ;in association with the bellows supporting frame, keybed, and decorative shell embodying a grill enclosing the treble action.

i The full nature of the invention will be understood fromthe accompanying drawings and the following description and claims:

Fig. lis a perspective view of the treble section with parts removed and portions broken away for illustrative purposes. o

v Fig. 2 is a plan view showing elements of the shift mechanism and associated valves. In the drawings there is shown a treble chassis or windbox preferably in the form of a' drawn metal shell having side walls l and a ported end wall H providingthe valve board. The open end 'of the windbox leads into the bellows I2 which are secured to a frame l3. The windbox is also secured about the edges of its side walls to the frame l3, preferably by the screws l4, and surrounded by the trimming bead I5 and a plastic tongues 19. The reed blocks are secured to the underside of the valve board by the reed block heads 20, which are slotted to slidably support the slide valves 2 la to 2ld. Said slide valves are provided with spaced ports therein for movement in and out of registry with the ports H for opening and closing one section of their respective ,reed blocks.

Mounted on the windbox to extend at an angle from one side thereof there is provided a keybed back plate 22 carrying a key slip 23 upon which is mounted and secured a channelled cushion rail 24 having spaced flanges 25, 26 supporting the natural key cushion strip 21 and sharp cushion strip 28, respectively. The outer edge of the key slip 23 is rolled upwardly and inwardly to form a decorative closure 29 for housing the guide bushings 80 and the ends of the natural keys 3|.

Also supported upon the keybed back plate 22 there is a spring rail 32 provided with a. plurality 4 Claims. (Cl. 84-376) end to one of said shift keys 52, 53.

of transverse slots 33 for receiving and anchoring one end of the respective key springs 34, one for each natural key 3i and each sharp key 35. Each natural and sharp key is mounted upon a suitable metal key body 36, 31 from which are bent the finger wires or valve lifts 38, 39, respectively. Said valve lifts are loosely connected at their free ends with the valve heads 40 arranged to seat upon the valve board H for opening and closing the respective ports thereof. Each key body 36, 31, is pivotally supported upon a hinge rod 4| and is maintained in its relative relation by the spaced bearings 42 of the key hinge supporting plate 43. Said plate 43 is secured to one side wall ID of the windbox to which the keybed back plate 22 is secured. Each end of the keybed back plate is supported and enclosed by the end arms 44 to which it may be screwed or clipped. in assembly.

For enclosing the valve action a decorative cover shell 45, provided with suitable grill work as partially indicated at 46, is secured about three sides of the windbox, being removably clamped in place by the recessed plastic molding l6.

Said treble section is provided with a central shift mechanism for controlling the slide valves 2|. For this purpose a pair of upstanding brackets 50, 51 are secured on the valve board I l substantially centrally thereof. Hinged to the upper end of each bracket there is a shift key 52 and 53 extending over and in line with the keys 3|, 35. Each of said brackets comprises a pair of spaced members formed with supporting legs to receive therebetween the shift trans-mission plates 7 placement, thereof in their overlapping relation.

Each of the plates 54, 55 is formed with an :elongated diagonal slot 51 into which a bent key finger 58 extends, each of said key fingers 58 being rigidly secured at its respective upper Upon depressing the shift key 52, the free end of its shift finger 58 is swung outwardly from the full line position shown at the left of Fig. 2 to the dotted line position and thereby slides its engaged transmission platelaterally to actuated position as indicated by the dotted lines. Thus, through pivotal movement of the shift keys their respective shift transmission plates are shifted laterally and relative to their bracket supports.

The plate 54 rides in a plane below the plate 55 and is provided with an aperture 59 for receiving the downturned end 80 of a, laterally extending oscillatory rod 6|. The plate 55 which extends above and overlaps th plate 54 is similarly provided with an aperture 52 for receiving the downturned end 63 of the oscillatory rod 64. Said upper plate 55 is also provided with a longitudinal slot 65 for permitting sliding movement thereof with the end 60 of the rod 6| extending therethrough. Similarly the lower plate 54 has its end recessed at 55 to permit it to clear the downturned end 63 of rod 64.

Consequently, the plates 54 and 55 may be shifted independently of each other to oscillate their respective rods 61, E4. laterally over the valve board H :through shift pins.

3. An accordion valve shift comprising a pair 7 of upstanding bracket members having a shift Said rods extend housing 67 mounted on said valve board. The-z ends of said housing provide suitable bearings, for supporting the rods BI, 64 in spaced parallel" relation. At spaced intervals on said rods there are provided shift pins 68, 69, 10, and II. The pins 58 and "H are secured to and depend from the rod 5| with their free ends engaged respectively in the slots 72 of the slide valves Zla and 2ld. For this purpose said shift pins are bent inwardly and downwardly so that their free ends are centrally disposed between the two rods SI, 64. Th shift pins 69 and 70 are secured to the rod 64 for engaging the slots 12 in the slide valves Zlb and 2| 0.

In this manner shifting of the plates 54, 55 oscillate the rods 6|, 64 respectively, rod 6| shifting valves Zia, Zld, and rod 54 shifting valves 2 lb and 210.

As it is necessary to prevent leakage of air through the slot 12 in the slide valves, the shift.- housing 61 is sealed to the valv board I l and is provided with a sealing cap 13 secured thereover. Thus, as shown in Fig. l the shift key 52 has been depressed swinging its key finger 58 outwardly to shift the plate 54 to the right to thereby shift valves 2 la, 2|d to port closing position. The key 53 being in its upper normal position the shift valves 2"), 2| 0 controlled thereby remain in their port open position.

The invention claimed is:

. 1. An ac ordion valv shift comprising a pair of upstanding brackets each having a shift key pivoted thereon a transmission plate slidably supported in each bracket, the end of one of said plates overlapping the other and each having an elongated diagonal slot, a shift finger secured to each key engaged in the slot of one of said plates for longitudinal displacement there- Qof upstanding brackets each having a shift key pivoted thereon, a transmission plate slidably supported in each bracket, the end of one of said plates overlapping the other and each having an elongated diagonal slot, a shift finger sekey pivotally mounted therebetween, each of said members having spaced legs with a series of internal notches therein, a transmission plate ex tending between said members and the legs thereof slidably supported in said notches, said plate having an elongated diagonal slot therein, a shift finger secured to said key extending into said slot for longitudinal displacement of said plate upon pivotal movement of said key, an oscillatory shift rod having an inturned end operably connected with said plate for oscillation thereby, and shift pins secured to said rod each having a valve engaging free end adapted to shift positions upon oscillation of said rod by the pivotal action of said key.

4. An accordion valve shift comprising a pair of upstanding bracket members having a shift key pivotally mounted therebetween, each of said members having spaced legs with a series of extending between said members and the legs thereof slidably supported in said notches, said plate having an elongated diagonal slot therein,

a shift finger secured to said key extending into said slot for longitudinal displacement of said plate upon pivotal movement of saidkey, an oscil- ,latory shift rod having an inturned end operably connected with said plate for oscillation thereby, shift pins secured to said rod having a valve engaging free end adapted to shift positions upon oscillation of said rod by the pivotal action of said key, and a closure box for said shift pins into which said rods extend to provide a bearing support therefor.

WILLIAM B. AHERN. ALBERT J. WALT.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,070,853 Berlin Feb. 16, 1937 2,192,857 Pancotti Mar. 5, 1940 2,274,376 Montenare Feb. 24, 1942 2,297,032 Stahl Sept. 29, 1942 FOREIGN PATENTS Number Country Date 351,954 Italy Aug. 27, 1937 

